Select saute mode on your pressure cooker. Melt butter in pressure cooker, and then add chopped onion. Cook until soft, around 3-5 minutes.
Add the minced garlic and cook for an additional one minute, stirring so the garlic does not burn.
Stir in 5 cups of vegetable broth, broccoli, carrots, salt and pepper.
Lock the lid into place and make sure the vent is set to seal. Put to high pressure for 1 minute.
When the cooking time ends, do a quick release of pressure. When the valve drops, carefully remove the lid.
In a separate bowl, whisk together additional ¼ cup of vegetable broth with ¼ cup of corn starch until there are no lumps.
Set the pressure cooker to sauté mode and allow soup to bubble. Slowly add cornstarch/broth mixture. Continue stirring until soup comes to a boil and thickens.
Turn the pressure cooker off. Add Greek yogurt and mustard, stir to combine.
Add cheese one handful at a time while stirring to prevent clumps.
Adjust salt and pepper to taste. Serve warm.
Servings 0